<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title></title>
    <style>
        * {margin:0;padding:0;}
        .scroll {
            width: 400px;
            height: 8px;
            background-color: #ccc;
            margin: 100px;
            position: relative;

        }
        .bar {
            width: 10px;
            height: 22px;
            background-color: #369;
            position: absolute;
            top: -7px;
            left: 0;
            cursor: pointer;
        }
    </style>
</head>
<body>
<div class="scroll">
    <div class="bar"></div>
</div>
</body>
</html>
